Monday, April 07, 2008

Ready for SNOPES: Does ethanol starve the poor?

Claim: The grain it takes to fill an SUV tank with ethanol could feed a person for a year. Harvests are being plucked to fuel our cars instead of ourselves.

Status: True

Source: TIME article The Clean Energy Scam

Evaluation: It was previously shown for a large SUV:

Fuel tank capacity: 31 to 39 gallons for a 2008 Suburban

Ethanol yield from corn: 2.8 gallons per bushel - found it here, originally sourced from Ethanol.com

Ethanol needed to fill the tank: Let's say 28 gallons* blended with 5 gallons of gasoline to make 33 gallons of E85 for the Flex-Fueled SUV.

Hence, 10 bushels of corn are needed to fill the tank of the Suburban with E85.

A bushel of shelled corn weighs 56 pounds (ear corn is 70 pounds per bushel, but I'm pretty sure that shelled corn is used in the process).

Hence, 560 pounds of corn are needed to fill the Suburban just one time.

Go here for analysis of a car or mid-size SUV.

A more detailed analysis than you need is below

But, I'm not done yet.

The Ethanol industry freely admits that the net yield of ethanol production is a mere 6% increase over the fuel used in the process. Knowing that, we find it takes 26.4 gallons of gasoline AND 560 pounds of corn to produce 28 gallons of ethanol.

In terms of cost - benefit, this comes down to it requiring 560 pounds of corn (The Cost) to reduce the amount of gasoline filling the tank of that SUV by 1.6 gallons (The Benefit). So, taking this inefficiency to account, we are essentially starving 17.5 people when we fill-up that SUV one time.

More fun facts from Big Eth

The Big Ethanol Lobby website (ethanol.org) says the following in their 2007 Ethanol Fact Book
Ethanol production yields many valuable human and animal feed co-products. A bushel of corn used in the fuel ethanol process produces 1.6 pounds of corn oil, 10.9 pounds of high protein feed (distillers dried grains, or DDG), 2.6 pounds of corn meal, and 31.5 pounds of starch that can be converted to beverages or sweeteners, or used to produce 2.5 gallons of ethanol.
First, I notice that Big Eth has revised downward its estimate of ethanol per bushel, from 2.8 to 2.5 gallons.

Next, I can't exactly follow the sentence structure, this statement could mean that we give up 31.5 pounds of starch (The Cost) for 2.5 gallons of ethanol (The Benefit); or it could mean, that it costs 1.6 pounds of corn oil, 10.9 pounds of high protein feed, 2.6 pounds of corn meal, and 31.5 pounds of starch for the benefit of 2.5 gallons of ethanol. I'll let someone who actually passed freshman english to answer that one for me.

*Parenthetically: Those 28 gallons of ethanol in the E85 contain 1/3 less energy than the gasoline it replaces. Therefore, 42 gallons of ethanol must be produced to provide the same power as a full tank of gas. That equates to 840 pounds of corn, or enough to feed a person for a year and one half. But I won't go into that, things are bad enough without the distraction.

2 comments:

Tim said...

Good job! :)

Anonymous said...

You forgot to figure for DDG produced and corn oil extraction. For every bushel you get 17 lbs DDG. Which now makes it 390 lbs of corn. Plus you have approx 2gal of corn oil per bushel possible which would be another reduction of about 140 lbs for a total of 250 lbs per e85 fill. so, at best, TIME's numbers for bushels per gallon are double what is ACTUALLY going on.